1. Field of the Invention
The present invention relates to a multi-band antenna, more particularly to an internal dual-band antenna for wireless local area network (WLAN) applications.
2. Description of the Related Art
Current internal antennas for WLAN applications, which are installed in notebook computers, are mostly based on a planar inverted-F antenna (PIFA) design.
Aside from the Bluetooth standard, the 802.11a/b/g standards are commonly used WLAN communication protocols. The 802.11a standard is for operation at frequencies ranging from 5.15 GHz to 5.825 GHz, whereas the 802.11b (or WiFi) and 802.11g standards are for operation at 2.4 GHz.
Since conventional antennas are not designed to be simultaneously compatible with the 802.11a/b/g communication protocols, multiple antennas are required to be disposed in a wireless device in order to ensure compatibility of the wireless device with each of the 802.11a/b/g communication protocols. Accordingly, aside from incurring higher component costs, more space is also needed in the wireless device to accommodate the antennas, thereby making it difficult to reduce the size of the wireless device so as to comply with the current trend toward miniaturization.